Stand mixers have been employed for decades to assist in the commercial and domestic preparation of food requiring mixing and/or kneading. Such stand mixers typically include a base or stand on which a rotatable turntable rests for holding mixing bowls of various sizes. In order to change from one size mixing bowl to the other, it is generally necessary to lift the turntable and reposition it in a different hole in the base. This task can be inconvenient, particularly for the elderly who may have difficulty lifting and/or repositioning the turntable and bowl, particularly if the turntable has become caked with batter or other food ingredients which may tend to cause the turntable to stick to the base.
Stand mixers also typically employ a pair of whippers which are attached to the front of the mixer and extend downwardly into the bowl containing food ingredients to be mixed.
While traditional whippers are effective in mixing, there is a tendency, particularly with thick batter or dough, to creep up the center bar that supports the whipper blades. This phenomenon, known as "dough creep" can potentially result in dough being driven up to the mixer head, fouling the gearing mechanisms, and potentially throwing dough and/or batter out of the bowl.
Prior stand mixers have also commonly used variable speed control mechanisms, such as dials, knobs, slide levers, etc. While such speed controls are effective for incremental speed changes, they do not generally provide a "burst" or rapid speed change which is frequently desirable to break up large clumps for a short period of mixing time only.
In general, stand mixers of the prior art have permitted the user to lock the head in the up and/or down position or to remove the mixer head from the stand, but not perform all three functions. Locking the mixer head in the up position is desirable because it prevents the head from falling back into the bowl. For purposes of carrying the mixer by the handle, it is desirable to be able to lock the mixer head in the down position. Furthermore, locking the mixer head in the down position alleviates bouncing by the mixer head in heavy dough. Removing the mixer head completely from the stand may often be desirable for individuals wishing to use the mixer as a hand mixer rather than a stand mixer.
Other problems inherent in stand mixers is the tendency for water, milk, batter, and other ingredients and liquids to collect in the base of the turntable and cause the bottom of the mixer bowl to stick to the bottom of the turntable, rendering removal of the bowl problematic.